Project Summary We propose the purchase of a preclinical imaging system combining capabilities of 2D and 3D bioluminescence and fluorescence imaging with x-ray computed tomography. Noninvasive light-based imaging techniques including bioluminescence and fluorescence imaging are powerful tools for monitoring disease process in animal models, reducing the number of animals required for research and increasing the true knowledge acquired for cancer and other diseases. Disease, compound biodistribution and molecular events can be quantitatively assessed noninvasively in live animals by means of reporter genes, probes and contrast agents. The IVIS SpectrumCT offers researchers industry-leading sensitivity for both bioluminescence and fluorescence, along with absolute data calibration and high throughput acquisition for longitudinal imaging studies. This instrument will support 9 NIH-funded Users from diverse research fields, including enhancing their current research capabilities with noninvasive, longitudinal visualization of disease processes deep within living animals, minimizing the need for invasive or terminal procedures. Multispectral imaging capabilities provides acquisition of anatomic, physiologic, functional and molecular information, all while keeping the subject comfortably positioned without harm. Availability of this instrument to these major users and many others will significantly advance the standard of research at Washington University, leading to new discoveries in disease processes, new diagnostic agents for cancer, lung injury, obesity, inflammation and osteoarthritis, as well as rapid assessment of therapeutic agents. The advanced preclinical imaging system will be housed in the Washington University Molecular Imaging Center within the Mallinckrodt Institute of Radiology, available for use by investigators at Washington University and in the surrounding research community. Highly experienced personnel will manage this instrument, training new users and providing expertise for experiment design. Overall, the availability of this instrument to NIH-funded investigators at Washington University and surrounding institutions will facilitate new discoveries in preclinical research for rapid translation to human medical uses.